title: A study of risk factors for hypospadias in the Rhône-Alpes region (France).
abstract: OBJECTIVE
  Hypospadias is one of the most common congenital urogenital malformations in males with a significantly increasing incidence over the past 20 years. The causes of this insufficient virilization of the genital tubercle are essentially unknown.
  
  
  METHODS
  A hospital-based controlled study was realized with 225 hypospadias cases at Debrousse Hospital, Lyon, using a detailed questionnaire completed during a consultation with the patients' parents and those of controls of the same age. The chi(2), the P-value, the odds ratios and the 95% confidence interval were assessed.
  
  
  RESULTS
  Hypospadias was found to be positively associated with genetic factors (as defined by the presence of other case(s) in the family in one case in four) and with neonatal low birth weight, fair-haired boys, maternal history such as viral infection during the first trimester, order of parity, toxaemia of pregnancy, delivery modality such as caesarean section, and environmental pollution.
  
  
  CONCLUSIONS
  These results show that aetiological factors of hypospadias are likely to be related to three main fields which interact: genes, the placenta and environmental factors.
authors.affiliation: INSERM U418, INRA UMR 1245, Claude-Bernard University 21, Debrousse Hospital, 29 rue Soeur Bouvier, 69322 Lyon Cedex 05, France.
authors.forename: A M
authors.initials: AM
authors.lastname: Morera
authors.forename: A F
authors.initials: AF
authors.lastname: Valmalle
authors.forename: M J
authors.initials: MJ
authors.lastname: Asensio
authors.forename: L
authors.initials: L
authors.lastname: Chossegros
authors.forename: M A
authors.initials: MA
authors.lastname: Chauvin
authors.forename: P
authors.initials: P
authors.lastname: Durand
authors.forename: P D E
authors.initials: PD
authors.lastname: Mouriquand